Don't Look in the basement is actually a very clever and well thought out exploitation flick that gets a bad rap because of its cheap quality and bad acting. Sure, it's not a masterpiece by anyone's standards but it is a very fun little B-film with a lot to offer and even a lot of creepy scenes that will stay in your head.
As I said, the acting could have been a lot better but that's the case with most exploitation so I can't really complain. The story is clever and has some great plot twists that will keep you guessing. I thought the gore was a lot of fun too. There's just something great about older gore films because they didn't have CGI back then so they had to actually set it all up themselves. See this one for a good time!